


Birthday Bash

by MizRootbeer



Category: Shall We Date?: Obey Me!
Genre: Birthday, F/M
Language: English
Status: Completed
Published: 2020-09-23
Updated: 2020-09-23
Packaged: 2021-03-08 04:21:33
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,495
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26609722
Author URL: https://archiveofourown.org/users/MizRootbeer/pseuds/MizRootbeer
Summary: Baku loves her boyfriend so when his birthday rolls around, Baku wants to make it perfect. In order to make it perfect, she has to do favor for all the brothers. It shouldn't be that hard right?
Relationships: Mammon (Shall We Date?: Obey Me!)/Original Female Character(s)
Comments: 1
Kudos: 18





	Birthday Bash

**Author's Note:**

> Another Obey Me comission. This is for yuukarinkazami on tumblr.

Baku was ready to put her plan into action. She planned for an entire month, and she wanted this plan to go off without a hitch. Making Mammon happy and giving him the perfect birthday would take a lot of work. And in order to get the perfect birthday for Mammon, she was going to have to get his brothers’ help. She had already talked to them about planning a surprise party. When the brothers had told her they were already doing one, Baku insisted on helping. She wanted to be the one who did most of the work. This was for her boyfriend, after all. 

The best gift Mammon could get would be his brothers respecting him and treating him like a king. How did she get them to do that? By helping out all seven brothers. It sounded simple, but she knew it wasn’t going to be easy, especially with Lucifer being up first.

“For the last time, I do not need your help,” Lucifer waved Baku off. “Most of the paperwork I need to finish is highly confidential. You’re not allowed to see it.”

“That’s okay,” Baku grabbed a few folders from his desk. “I can handle the detention list, the student council forms, and the club applications. Also, I got you a little something for your desk.”

Baku placed the folders in her bag and then grabbed a small box. Lucifer raised an eyebrow as Baku opened it up. 

“It’s called a Newton’s Cradle,” She explained. “Watch.”

She placed it on his desk and grabbed the ball at the end. She let go, and just like intended, it forced the ball on the opposite end to push away. It came back, and the same thing happened. Lucifer stared at it intensely. For what seemed like ages, he was silent, and then he looked at Baku.

“What do you want exactly?” He asked.

“Be nicer to Mammon and if you could increase the credit limit on Goldie.”

Lucifer stared at Baku before going back to the Newton’s cradle.

“You’ve got a deal,” Lucifer handed her another folder. “I also need someone to do inventory.” 

Baku smiled as she took the fourth folder and headed out of Lucifer’s office. She was surprised at how well that went. As she headed back to the House of Lamentation, her D.D.D dinged. She reached into her pocket and saw it was Mammon. She grinned but didn’t answer. She was too busy. Next up was Levi. He would be easy since he rarely left his room, and he could always find him. She dropped the folders off at her room before heading over to Levi’s. She knocked on the door.

“What’s the password?” Levi asked.

Baku sighed. 

“Ruri-chan is best waifu,” Baku replied. 

Levi opened up the door before going back to his couch. He put his headphones back and went back to playing his game. Oh great, he was in another one of his moods. Baku joined him on the couch, taking a look at the game he was playing. It was one of those first-person shooter games featuring anime looking characters. Yeah, sounded like something Levi would be into. Bake waited for a moment, not wanting to interrupt Levi’s game. 

“You want something,” Levi broke the silence, his eyes still on the television screen. “What is it?”

“It’s Mammon’s birthday,” Baku said calmly. “I want you and the other brothers to be super nice to Mammon. I’ll do whatever you ask if you’re just nice to him.”

“You know the Spring Fairy Ruri-chan figure?” Levi still paid attention to his game. “It’s a limited edition, they’ve only made five hundred of them. Stand in line with me. We’re going in an hour.”

“Oh, okay,” Baku said. “They have some of those exclusive Mononoke Land blind boxes. I want to grab a few.”

“Awesome, let me finish up this game.”

When his game finished, Levi and Baku got ready to head off to the store. As Baku got ready, her D. D. D rang again. She grabbed it and saw it was another text from Mammon. Sighing, she put it back into her pocket. She promised herself she’d text him right after she was done with Levi. It probably wouldn’t take that long.

* * *

  
Okay, so four hours had been lost.

The good news was that Levi got both editions of the new Ruri-chan figure, and Baku managed to score a limited edition blind box item. The bad news? Baku had lied to Mammon. He had texted her too many times for her to ignore. She read them, wincing as she realized how worried he was. This wasn’t normal for them; they were a couple who texted each other frequently. Baku would have told Mammon the truth, but she wanted all this to be a surprise. So instead, she lied, saying she had extra homework. 

Baku didn’t want to dwell on her feelings of guilt. There would be time for that later. Right now, she had to move onto Satan.

“I had a feeling you were planning something,” Satan said when she came to him with her request. “And you say you’ll do anything?”

“Within reason,” Baku added.

“Lucky for you, I have just the thing in mind. I’m looking for a limited edition first copy of The History of and Evolution of Curses by Belladonna Blackholm. Help me find a copy, and I’ll agree to your terms.”

Again, Baku thought this would be a simple trip. What as one visit to the bookstore?

Five.

They ended up visiting five bookstores and two libraries. Baku never wanted to see a book again after this. When they had finally hunted down a copy of the infamous tome, the seller had doubled the price. Satan was hellbent purchasing the book, and Baku, wanting to end this trip, added her Grimm. The greedy merchant was placated, and the two of them headed back home. 

“You’re never, ever, ever getting rid of that book,” Baku told Satan. “If I heard you sold it, I’ll find you.”

“I won’t,” Satan promised. “I’ve been searching for this book for one hundred years.”

“I believe it,” She sighed. 

Baku was ready to ignore her D.D.D when Mammon texted. Seeing the frowny faces hurt a bit. This would all be worth it. Mammon was going to be the happiest demon in the Devildom by the time she was done. Yawning, Baku replied she was studying with Satan. It wasn’t a complete lie, but she still felt a tad guilty. Hopefully, helping Asmo with his favor would take her mind off it.

“A modeling gig? Asmo, come on,” Baku rubbed her temples. 

“Please, my sweet, beautiful Baku?” Asmo clasped his hands together and batted his eyelashes. “I’d be forever so grateful, and I’d even give you a smooch.”

“Hey, what did I say about the kissing?” Baku placed a hand up as Asmo tried to move forward. “I’m dating Mammon, not you.”

“Don’t remind me,” Asmo grumbled. “It’s not fair that he got you, and I didn’t. If only there was some way I could regain my joy. If only---”

“Okay, fine!” Baku sighed. “I’ll talk to his agent and see what I can do.”

Getting the manager on the phone was the easy part. Trying to convince him to let Asmo be on the cover for Majolish? That was going to take some fancy talking.

“Yes, but he’s the Avatar of Lust. Have you seen his Devilgram? Take a look right now and tell me he’s not front-page material,” Baku paused. “Yes, he does his own makeup. Yes, his skin looks that good. Still not convinced? Look, put Asmo on the cover, and I’ll get Mammon to do three extra photoshoots for you. We have a deal? Great!”

“Aiee, Baku you’re the best!” Asmo hugged her. “I love, love, love, love you so much right now!”

“Yeah, yeah, yeah. Just promise me you’ll keep up your end of the deal, okay?”

“I promise beloved Baku,” Asmo cooed. “Oh I better get ready!”

Baku had to take a small break after dealing with Asmo. All of these promises and running around was making her tired. It would be worth it, of course, but she had to sit down for just a second. Since she was sitting, she reached into her pocket and looked at her D.D.D. She had gotten ten more texts from Mammon. She honestly wished she could tell him what she was doing, but this had to be a surprise. It was going to be the best surprise Mammon could ever get! Just one small break, and she’d be back on her feet. Besides, Beel was next. He was easy to please.

“So you just want Mammon to never steal your custard again?” Baku asked him. 

“And dinner at Hell’s Kitchen.” Beel added.  
“Alright, I can do that,” Baku said with a smile. “Just gives me a heads up for when you want to go eat, okay? I gotta save up my Grimm.”

Last was Belphie, and Baku was sure his request would be something simple. Belphie wasn’t a complicated person; he just wanted to nap. Baku could respect that. 

“Belphie, wake up,” Baku said.

“Meh,” Belphie pulled the covers over his head. 

“Belphie, wake up!” Baku pulled the covers away from his head.

“I don’t wanna,” Belphie groaned, covering his face with a pillow.

“Belphie, I’m not going to go away until you talk to me,” Baku grabbed the pillow. “It’s about Mammon’s birthday. I want you and the brothers to be nice to him, so I’m willing to do anything to make that happen.”

Belphie moved his arm away from his face and looked at Baku.

“Anything?”

“Within reason. Nothing that will kill me,” Baku added. “So, what will it be?”

“Do all my chores for the day,” Belphie said. “I’ll write them down on a piece of paper, and then you do them all.”

“Okay, that sounds good.”

Baku regretted agreeing to do all of Belphie’s chores. When he had said do tasks, Baku had thought he meant cleaning the dishes or doing the laundry. Doing chores in the Devildom meant cleaning up after bats, removing snakes from dungeons, and trying to get Cerebus’ teeth clean. By the end of the day, Baku was exhausted. Every bone in her body ached, and she was dirty. Today had been such a nightmare, but it was all over now. She had done her job and gotten all the brothers to promise to be nice to Mammon. 

Sighing, Baku opened up the door to her room. There was a package on the bed with her name on it. She walked over to her bed and opened it up. She gasped when she pulled out a beautiful cocktail dress. It was a dark, shimmery purple with a silver lily-shaped clasp on the left shoulder. Baku had never seen such a pretty dress before. There was a note pinned to it.

“I don’t know if you’re mad at me or not, but I still wanted to get you this dress for the party tomorrow. I want everyone to see how beautiful you are,” Baku read. “With love, Mammon.”

All the guilt that she had been feeling came back, and Baku felt awful. Poor Mammon. At least she could tell him why she had been avoiding him tomorrow. Right now, she just wanted to take a nice long shower. Tomorrow, she’d make it up to him and make sure he had the best birthday of all time.

* * *

  
Baku entered the dining room, wearing the dress Mammon bought her. She had found a pair of tights, and Asmo let her borrow a pair of purple heels. She felt pretty, but she cared more about Mammon. 

“Hey, Baku!”

Mammon made a beeline for her the moment he saw her. His jaw dropped when he got close and saw her in the dress. Even though they had been dating for a while, Mammon would still get red-faced around her. God, he was so cute. It made for him adorable in her eyes, and she loved to tease him about it. 

“If you keep your mouth open like that, the flys will get in,” Baku said.

“I’m just staring because I have good taste,” Mammon grabbed Baku. “Now c’ mere, it’s time for my birthday kiss.”

Baku giggled as Mammon dipped her low and kissed her. Asmo whistled; Mammon gave him the bird. Mammon pulled her back up, and Baku smiled at him.

“You’re with me all night tonight,” Mammon told her. “We didn’t get a chance to spend any time together yesterday, so I want to make up for lost time.” 

“About that,” Baku fiddled with a loose strand of hair. “Since it’s your birthday, I wanted everything to be perfect. So I asked all your brothers to be nice to you. To get them to agree to my plan, I had to do a bunch of favors for them.”

Mammon already loved Baku but finding out about her work on his behalf made him love her even more. He kissed her again abruptly and then picked her up.

“You’re the most perfect girlfriend in the entire Devildom,” Mammon said. “I couldn’t ask for anything more today. Let’s go party.”

Baku felt tired, but she didn’t care about her exhaustion. All she cared about was Mammon’s happiness. She wanted to be with him at this moment. Smiling, she looped her arm with his, ready to start the party.

Lucifer must have been in a good mood because he presented Mammon with an extended credit limit and even got another gift. He gave Mammon a gorgeous leather coat with fur trim on the collar. Mammon tried it on, and it fit like a glove. Baku noticed it looked a little bit like Lucifer, but she decided not to mention it. Mammon was enamored with the jacket, doing a bit of modeling for the party-goers.

Levi surprised Baku. He had four gifts for Mammon. The first one was the DVD boxset of Cowboy Bebop, the one anime that Mammon loved. He told Baku he was like Spike, a bad boy who was always looking for trouble. The second box featured a figure of Ed with her dog Ein. The last two boxes featured T-shirts featuring the characters.

“Don’t get it twisted, I still think your anime tastes are normie level, but Cowboy Bebop is a god tier anime. You have my respect.” Levi said.

Next up was Satan. Of course, it was a book. Three books, to be precise. They were leather-bound with golden letting on the front of the cover. 

“Whoa, is this the whole Lord of the Rings trilogy?” Mammon asked. “These look expensive. Where did you find these?”

“I have my ways,” Satan said with a simple shrug.

“Dude, this is a really great gift,” Mammon admitted. “I kinda feel like I shouldn’t take these, you should have these. You’re the book nerd.”

“No, I bought these specifically for you,” Satan said, placing a hand on the books. “While you’re not an avid reader like me, I know you love this series. These are yours, and I trust you to take care of them.”

“Thanks Satan, I really mean it,” Mammon smiled. “If you ever want to borrow them, I promise I’ll let you.”

“My turn, my turn!” Asmo declared. “Hurry and open it, everyone has to see it’s a beauty!”

The wrapping paper was pink with glitter, and the ribbons were very ornate. Mammon carefully opened the gift. 

“Why are you being so careful?” Baku asked.

“Asmo wrapped it really nice, I don’t want to ruin it completely,” Mammon admitted, his cheeks turning red.

God, he was so sweet.

“Is this a scarf? Wait, Asmo, did you craft this? It looks amazing,” Mammon put it on. “And a bottle of Dantalion cologne? Wow.”

“Isn’t the best gift? That cologne is high-end, it’ll make Baku go crazy,” Asmo nudged Mammon. “You’re welcome.”

“Yeah, thanks,” Mammon started blushing more.

Beel’s gift was simple. It was a gift card for Hell’s Kitchen.

“There’s a thousand Grimm on there,” Beel said. “I know you don’t eat as much as me, but I figured you could take Baku on dates there. I was going to get you some fancy chocolates, but I was afraid I’d eat them.”

“Wow, thanks, Beel,” Mammon said. “I know what we’re doing for dinner tomorrow. I hope you’re not busy, Baku.”

“I’m not,” Baku smiled. “It’s a date.”

Last was Belphie. They found him at the table, trying to nap. Baku snuck up behind him and started tickling him. Belphie shot up, pushing her away.

“No fair!” Belphie grumbled. “I was having such a nice dream, and you woke me up.”

“Hello, this is a birthday party, Belphie,” Baku playfully poked Belphie’s cheek. “Wake up, enjoy the party and the cake. You’ll want some before Beel gets to it.”

“Yeah, yeah, yeah,” Belphie yawned. “Alright, here’s Mammon’s gift. I hope you enjoy it, it’s personal.”

Belphie held up a box shaped like a little house. Baku recognized the box; it was from Create-a-Creature. Mammon opened up the box and found a teddy bear that looked just like him. It was adorable!

“I’m normally not a person who likes cuddly, cute stuff, but I have to admit, this is amazing,” Mammon gave the bear a hug. “Good for hugging.”

Baku couldn’t stop smiling. She was still feeling sleepy, but she was okay with that. Mammon was having a great birthday, and each of his brothers had gotten him wonderful gifts. She had hoped they would just be nice to him, but she was elated that they had brought him thoughtful gifts. All the hard work from yesterday was worth her aches and pains. Seeing Mammon smile was all she needed.

“Hey, what are you smiling about?” Mammon asked her.

“I” m smiling because of you,” Baku nudged him playfully. “You’re my boyfriend, so I’m happy to see you happy. It’s your birthday, it should be perfect.”

“I normally would agree, but you know, all I really want is you,” Mammon admitted. “It’s awesome that Lucifer increased the credit limit on Goldie but honestly, all I need is you.”

“When did the Great Mammon become so sappy?” Baku asked.

“Since you came into my life,” Mammon pulled Baku into his arms. “And now it’s time for a birthday kiss.”

“I thought I already gave you your birthday kiss,” Baku asked, moving his glasses to his head. 

“Yes, but it’s my birthday, right? That means I get whatever I want and what I want is more kisses from my adorable girlfriend.”

Baku pulled Mammon close to her and kissed his lips. He closed his eyes, a purr escaping him. Baku chuckled as she went to pull back, but Mammon pulled her into another kiss. After that, Baku suggested cutting the cake before Beel got to it. Mammon demanded Baku feed him, and she did before squishing some onto his face. Asmo snapped a picture.

“Send that to me,” Baku said. “I want it to be my background on my D.D.D.”

“At least the cake is good,” Mammon tried to lick his nose. “Your turn now.”

Baku squealed as Mammon walked towards her with his dirty fingers. She tried to run, but there was no escape from getting cake on her face.

“You’re so lucky it’s your birthday!” She said, using her finger to get some icing. “And you’re also lucky you’re extremely cute.”

“Speaking of which, I need another birthday kiss,” Mammon puckered up.

“Okay fine,” Baku sighed dramatically, but she was smiling. “Come here.”

Again, the two of them kissed, and this time, Mammon picked her up. He twirled her around before setting her back down. He pressed his forehead against hers, a small smile on his face. 

“I can’t thank you enough,” He said softly. “I really can’t. This has been the best birthday I’ve ever had.”

Baku squealed again, this time with delight. Her exhaustion meant nothing as her heart swelled. All she wanted was Mammon to be happy, and here he was, having the best birthday ever. For a demon to say this birthday was his best meant a lot; Mammon had been around for thousands of years, how many birthdays had he had? 

“I would do all that work again,” Baku told him. “Just so you’d enjoy your birthday. I may be tired, but I don’t care. Happy birthday Mammon.”

“After the party, we’re heading straight to bed,” Mammon said. “Don’t bother arguing with me. It’s my birthday, you have to do what I say.”

“Oh well, if I must rest after the party,” Baku said. “Then I guess I must. But for now, we must enjoy your party.”  
Mammon gave Baku one more kiss before looping his arm with hers and then headed back to the others. 


End file.
